What is macular degeneration (Yellow Spot Disease)?
Macular degeneration (Senile macular degeneration, age-related macular degeneration AMD) is a degenerative retinal disease and is the most common cause of vision loss in individuals over 65 in developed countries.
What is the retina?
The retina is a thin, light-sensitive layer that covers the inner back surface of the eye. Light entering the eye is focused onto the retina by the cornea and lens. This image formed on the retina is converted into electrical signals and transmitted to the brain via the optic nerve.
What is the macula?
The macula is a small central part of the retina responsible for central vision and color vision. It allows us to read, drive, and see fine details. The peripheral retina outside the macula plays a role in peripheral and night vision.
Who gets age-related macular degeneration (Yellow Spot Disease)?
Macular degeneration is most commonly seen after age 55 and increases with age.
What are the types of age-related macular degeneration (Yellow Spot Disease)?
There are two types: dry and wet (exudative). Typically, the dry type develops slowly and painlessly, while the wet type occurs in individuals who already have the dry type, in more advanced stages. Dry type develops over decades, whereas wet type can develop within months, weeks, or even acutely. Dry type is caused by accumulation of metabolic deposits (drusen) under the retinal pigment epithelium, while wet type results from the formation of new blood vessels (choroidal neovascular membranes) under the retina.
What causes age-related macular degeneration (Yellow Spot Disease)?
Macular degeneration is often a result of natural aging. Over time, retinal tissues deteriorate and thin, leading to loss of macular function.
In about 10% of macular degeneration cases, aging of the retina and leakage from small blood vessels supplying the retina contribute. In the resulting scar tissue, abnormal new vessels often form. Blood and accumulated fluid damage the macula, causing vision deterioration and blurriness. Extensive scar tissue formation can lead to severe central vision loss.
Less common causes include trauma, infection, and inflammation. The disease can also be hereditary.
What are the symptoms of age-related macular degeneration (Yellow Spot Disease)?
Symptoms include vision deterioration, central vision loss (scotoma or blind spot), difficulty reading, increased need for light, decreased color vision quality, and seeing lines as broken.
Macular degeneration can cause the words in the center of a page to appear blurred.
The most prominent complaint is blurry or distorted central vision. Difficulties in reading, near work, and driving may be noticed. A person with macular degeneration may describe blurry letters, jumbled lines, or black/empty spots in central vision.
Macular degeneration can also reduce color vision. While central and color vision are impaired, peripheral vision remains unaffected, so the disease does not lead to complete blindness. If the disease affects only one eye, the healthy eye may compensate, and symptoms might not be noticed.
How is age-related macular degeneration (Yellow Spot Disease) diagnosed?
Although clinical examination (dilated eye exam, Amsler Grid test, etc.) is usually sufficient, additional tests such as fundus autofluorescence, optical coherence tomography (OCT), and fluorescein angiography can help distinguish between wet and dry types of macular degeneration.
An ophthalmoscope, a lighted device, is used to examine the retina. Some specialized tests may also be applied. The Amsler grid test evaluates central vision deterioration or blind spots by having the patient look at a grid-like paper. Color vision tests help assess macular damage in patients who cannot identify numbers within colored shapes.
Optical coherence tomography (OCT), a harmless test, provides highly precise diagnosis.
If macular degeneration is detected, fluorescein angiography may be used to evaluate blood vessel leakage. A dye is injected into the patient’s vein, quickly reaching the eye, and photographs of retinal vessels are taken to assess the extent of damage.
What happens if age-related macular degeneration (Yellow Spot Disease) is left untreated?
In wet type macular degeneration, the disease progresses more aggressively, and vision loss occurs faster. If untreated, symptoms worsen, bleeding may occur, and in advanced stages, it can lead to blindness.
How is Yellow Spot Disease treated?
Treatment aims to slow or stop disease progression and improve quality of life. Early measures include vitamins A, C, E, beta-carotene, zinc, a diet rich in green leafy vegetables and fish, and avoiding risk factors such as smoking. Wet type macular degeneration is treated with intraocular injections of VEGF inhibitors (ranibizumab, bevacizumab, pegaptanib), or if not suitable, laser coagulation and photodynamic therapy.
Assistive Devices for Low Vision
Individuals with advanced macular degeneration who do not benefit from standard treatments may use assistive devices. Magnifying devices, telescopic glasses, handheld magnifiers, good bright lighting, and large print books, newspapers, and magazines can help.
PREVENTION IS THE BEST MEDICINE
Because the disease can progress unnoticed, regular eye exams are the only effective method for detecting macular degeneration. Early diagnosis improves treatment effectiveness, making it crucial to prevent severe vision loss. Regular follow-ups are especially important for older adults and individuals with a family history of retinal problems.
If you have difficulties with central or color vision, you should undergo a comprehensive eye examination.
References
- Arroyo JG, Trobe J, Schmader KE, Libman H. Age-Related Macular Degeneration: Clinical Presentation, Etiology, and Diagnosis. In: Post TW, ed. UpToDate. Waltham, MA: UpToDate. https://www.uptodate.com/contents/age-related-macular-degeneration-clinical-presentation-etiology-and-diagnosis
- Maturi RK, Dahl AA. Nonexudative (Dry) Age-Related Macular Degeneration (AMD). In: Nonexudative (Dry) Age-Related Macular Degeneration (AMD).
- Gheorghe A, Mahdi L, Musat O. AGE-RELATED MACULAR DEGENERATION. Rom J Ophthalmol. 2015;59(2):74-77.